Compressor structure



May 17, 193 8. L. H. BROWNE 2,117,601

I COMPRESSOR STRUCTURE 3 Filed Aug. a, 1936 INVENTOR l ind sa yIZBrawne.

VMM'i ATTORNEYs Patented May 11, 1938 UNITED STATES PATENT OFFICE 72,117,601 COMPRESSOR- STRUCTURE Application August s, 1936, Serial No.94,930

3 Claims.

, This invention relates to improvements in compressor structures. u

An object of the invention is to provide an improved piston structure. 4

Another object of the invention is to provide a piston and .connectingrod structure suitable for use in compressors and including improvedmeans of joining the rod and piston.

Still another object is to provide a structure of the above type inwhich the wrist pin is secured without the use of bosses -in the pistonbarrel, and in which working of the wrist-pin into contact with thecylinder wall is rendered impossible.

A further object isto provide a structure of the above characterincluding a suction valve on the piston, the valve, piston andconnecting rod being fastened together by a single securing means.

Another object is to provide an improved oil baffle in the piston.

A still further object is to provide a structure of the above type whichmay be cheaply, easily andaccurately manufactured.

Other objects and advantages of the invention will become evident duringthe course of the following description in connection with theaccompanying drawing in which:

Figure 1 is a vertical sectional view showing the piston and upper endof the connecting rod in place in a suitable compression cylinder;

Figure 2 is a vertical sectional view showin the parts separated toillustrate the assembly;

Figure 3 is a side elevation of the piston barrel;

Figure 4 is a top view of the same;

Figure 5 is a side elevation of the ring plate valve; 3 1

Figure 6 is a plan view of the same;

Figure 7 is a detail side elevation of the connecting rod and trunnionstructure; and

Figure 8 is a top view of the trunnion member.

traldischarge passage l6 through the plate H iscontrollable by anupwardly opening spring leaf valve ll of a type fully described andclaimed in the above-mentioned application.

A piston I8 is slidable in the cylinder lland is adapted to bereciprocated by any suitable type of crank (not shown) through themedium of a connecting rod IS. The body of the piston consists of acylindrical barrel 20 shown in detail in Figure 2, and having a flathead 2| pierced by a central hole 22. The outer face 23 of the head 2|has therein an annular groove 24 from which holes 25 lead into theinterior of the barrel 20. A forked member 26, shown in detail inFigures 2, '7 and 8,-has cylindrically curved side legs 21' and 28adapted to fit accurately, in the cylindrical interior of the barrel 20..A short cylindrical boss 29 on the top of the member 25 is adapted toengage the inner face of the head 2|, and a central hole 30 through theboss 29 is tapped to-accommbdate a clamping screw 3|,- Figures 1 and 2.

A hollow wrist pin 32, supported-in the legs 21 and 28, has rotatablymounted thereon a bushing 33 in the upper end 34 of the connecting rodl9. An oil hole 35 is provided through the top of the rod-end 34 andbushing 33. The lower end 36 of the rod I9 has secured thereto an oilsplasher 3'! and is lined with a bushing 38 having grooves 39 adapted toreceive lubricant through an inclined oil-hole 40. The upper end 34 ofthe connecting rod and the bushing 33 may be made with a running fitbetween the inner surfaces of the legs 21 and 28, the latter thuspreventing side-play of the connecting rod.

In assembly, the member 26 is inserted in the barrel 20, 'the tappedhole 36 registering with the hole 22 in the piston head 2|. A ring plate4| of thin metal, shown in detail in Figures 2, 5 and 6, is placed onthe flat upper face 23 of the head 2| so as to overlap both the innerand outer edges of the annular groove 24. A narrow spacer washer 42,slightly thicker than the ring plate 4|, and of outer diameter slightlyless than the inner diameter of the ring plate, is placed within thelatter on the face 23. The clamping screw 3i, which has a cylindricalhead 43 larger than the inner diameter of the spacer washer 42, isinserted through the washer 42 and hole 22 and screwed tightly into thethreaded hole 30 in the forked member 26. The latter member, carryingthe wrist pin 32 and attached connecting rod I! as previously explained,is firmly clamped against the inside of the head 2|, while the spacerwasher 42 is clamped between the screw-head 43' and the face '23.

The overlapping screw-head 43 retains the rin'g-plate ll on the piston,and the washer 42 acts as a concentric guide for the plate. Due to thefact that the washer is slightly thicker than the plate 4|, the latteris allowed a small vertical play under the screw head 43. The plate thusconstitutes a valve normally closing the groove 24. During the suctionor the downward stroke of the piston 20 in the cylinder l gas passesupward through passages 44, Figure 8, between the flattened verticalfaces 45 of the member 26 and the bore of the barrel 20 into the annularspace46, Figure 1, around the boss 29, from which it passes through theholes 25 into the groove 24, raising the ring plate valve 41 andentering the cylinder around the periphery of the valve.

While the ring platevalve, 4| ismade of thin metal, as stated, the fullportage aroundthe entirecircumference of the valve allows ample valveopening within the small free rise provided by the use of the spacerwasher 42, so that normally no flexing of the valve plate is necessary.The large inlet area, lightness of the valve plate and limitedmovementof the latter allow the valve to operate positively, quietly andwith a minimum of resistance to the flow of fluid, making it especiallyadapted to high speed compressor operation at high volumetricefliciency.

The exact valve lift desired may readily be secured in manufacture bymaking the washer 42 of material thicker than the material of the ringplate valve 4| by the amount of the desired lift. It is obvious that ifdesired, however, the screw 3| may be made with an integral shouldertaking the place of the washer 42.

To prevent an undue amount of lubricant being carried into the inletpassage, a .baiile 41, Figures -1 and 2, is disposed in a-groove 48 inthe lower part of the barrel 20.. This baille 41 is preferably made inthe form of a disc of resilient sheet metal having a slot 49, Figure 2,to accommodate the connecting rod l9, and split at one point 59 to allowthe battle to be sprung around the rod andsnapped into place in thegroove .48. External 011 grooves such as 52 and 53 may be provided onthe barrel 20, serving to regulate the supply of lubricant to thecylinder walls and to aid in sealing the piston against leakage ofpressure.

From the foregoing description it is evident that the inventioncomprises a simple structure inwhich the piston, the connecting rodattaching means and the inlet valve are secured accurately in propermutual relation by the single clamping screw 3|. The individual partsare simple and lend themselves to easy and uniform manufacture byautomatic or semi-automatic machinery.

The barrel 20 may readily be. made from bar stock or the like, due toits lack of internal bosses VVl1ile the invention has been described inpreferred form it is not limited to the exact structures illustrated, asvarious modifications may be made without departing from the scope ofthe appended claims.

What is claimed is:

1. In a compressor, a piston structure comprising in combination acylindrical barrel having a head, said head being formed with inletpassages therethrough, a, valve on said head adapted to control saidpassages, a forked member in said barrel and engaging said head, awrist-pin in said forked member, the cylindrical wall of saidbarrelclosely embracing the sides of said forked member whereby said wrist-pinmay be retained therein, and common means to retain said valve on saidhead and to secure said forked member in said barrel.

2. A piston structure comprising in combination, a cylindrical barrel, aflat head on said barrel, said head being formed with an annular groovein the outer face thereof and a plurality of passages from said grooveinto the interior.

of said barrel, 9. ring plate valve disposed on said head and overlyingsaid groove, a-forked member in said barrel, a wrist pin in said forkedmember, a screw extending through said head and threaded into saidforked member'to secure the same in said barrel, said screw having ahead overlapping the inner edge of said-ring plate valve, and spacingmeans under said screw head and within said ring plate valve, saidspacing means being thicker than said-valve whereby said valve may haveplay between said outer face and said screw head.

' 3. A piston structure comprising a cylindrical barrel having aninternal groove formed therein,

